I think it comes down to 2 things.I'm not quite sure why all this arguing over the Discovery timeline. you can't compare the look to TOS, TOS was made in the 60's with what was available at the time. Of course Discovery isn't going to look like that. If TOS were made with all the FX advances it would look different too. I'm still going to wait for news when the start date is and watch and see where things go from there.
1 It's very close to "TOS" time which makes suspension of disbelief harder. If this had been set 20 to 25 years further in the past I think people would acept it more because then you would see the show more like it's evolved from the "Enterprise" time and "TOS" could still exist in it's kind of magical 60's landscape that is never really dealt with in regards to the other Prime universe shows.
2 The Klingon look seems to be a big depature from what had became the accepted look since "TMP." I think their look at became just as iconic as Vulcan ears so that is going to unsettle people.
Jason